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Jaguars' situation goes from bad to worse: NFL Week 7 injury updates

Maurice Jones-Drew is on pace for 1,100 yards, his lowest output since 2008. (Marcio Jose Sanchez/AP)

Sunday started off well enough for the Jaguars: They raced out to a lead, on the road against Oakland. But things turned sour in a hurry.

Not only did the Jaguars cough up that lead and lose in overtime to Oakland, but they did so with star running back Maurice Jones-Drew and starting quarterback Blaine Gabbert on the bench. Both players suffered potentially serious injuries, forcing Jacksonville to turn to its backups for the rest of that Week 7 game and possibly beyond.

Now's not the time to be ailing, either, if you're the Jaguars. Next up on the schedule: a trip to Lambeau Field to take on the surging Packers.

Will Gabbert or Jones-Drew be available for Jacksonville's Week 8 matchup with Green Bay? SI.com injury expert Will Carroll returns to help us sort through Sunday's NFL carnage:

• Maurice Jones-Drew, RB, Jaguars (foot): Jones-Drew was carted off the field following his second carry of the day. Jacksonville announced that he suffered a foot injury, and he did not return.

Carroll:There was a quick shot of the Jags trainers re-taping Jones-Drew's ankle, then they showed him being carted off (in the cab of the cart, oddly.) Normally, trainers don't re-tape someone unless they're going back in, but it's a big clue that this is a mid-foot issue. Those of us who aren't up on our anatomy do one thing when we get hurt -- point. Jones-Drew likely said he hurt his ankle, rolled it, perhaps. The trainers reacted quickly, fixing the easily fixed, but when Jones-Drew stood, the pain likely returned. He left the stadium on crutches and is headed for tests. The worst-case scenario is a mid-foot fracture which would essentially end his season. There are lots of better scenarios as well.

Who takes his spot?: Rashad Jennings, the starter heading into the season as Jones-Drew worked back from his holdout, would reclaim No. 1 duties with MJD sidelined.

• Blaine Gabbert, QB, Jaguars (shoulder): Gabbert's injury is to his non-throwing (left) shoulder. Gabbert took a hit from Oakland's Tommie Kelly, then later gave way to Chad Henne.

SI.com injury expert Will Carroll:Gabbert injured his non-throwing shoulder, much in the vein of Jake Locker. It didn't appear as violent an injury as Locker's, but he wasn't able to return. While it's not the throwing shoulder, it is key to the throwing motion and a QB often gets hit and/or lands on it, so it's very tough to play through any kind of injury. Scans Monday will give an idea of what exactly is going on, but the fact that he couldn't come back for the second half is telling.

Who takes his spot?: Henne will play if Gabbert cannot play, but Jacksonville would have to add a backup QB in that scenario. Re-signing Jordan Palmer or plucking John Parker Wilson off the practice squad are two options.

• Shonn Greene, RB, Jets (head/shoulder): A huge hit by New England's Brandon Spikes staggered Greene in the fourth quarter, then he took another shot in OT that left him slow to get up.

Carroll:Greene took one nasty hit, a helmet-to-helmet job that is going to lighten Brandon Spikes' wallet, and then another. The Jets will need to bring Greene back through the concussion protocol, so it's impossible to predict the timing on this.

Who takes his spot?: The Jets already find themselves light on running backs. If Joe McKnight stays healthy, he would be next in line at the moment.

• Jeff Faine, C, Bengals (hamstring): Faine left Sunday night's Cincinnati loss to Pittsburgh with a hamstring injury and did not return to the game.

Carroll:The Bengals' center -- an injury replacement himself -- injured his hamstring and had to be replaced. There's no word yet on severity, but the hamstring is more important for the center due to his squatting and footwork than other offensive linemen. Even a mild hamstring strain could keep Faine out a matter of weeks.

Who takes his spot?: Rookie Trevor Robinson jumped in for Faine, but the Steelers took advantage of the resulting drop-off in blocking ability.

• Trent Richardson, RB, Browns (ribs): Richardson entered Week 7 banged up, then told reporters that his injury was more severe than most people realize.

Carroll:The Browns say that Richardson did not re-injure himself or have a new injury, but that he was merely ineffective. I call this semantics. Richardson couldn't play in his reduced condition, but the Browns didn't know this going in. An old-style flak jacket didn't help, either, with only a couple hits convincing Richardson that he needed to be off the field. Maybe he'll try a more advanced flak jacket, like Michael Vick or Robert Griffin, or maybe he'll have to wait a couple weeks for his ribs to heal. I'd guess the Browns will be on the phone this morning looking for the former, but the way this has played out really should worry Browns fans. If he was this injured going in, he should never have gone in.

Who takes his spot?: Montario Hardesty picked up carries Sunday, and he would start should Richardson have to sit.

• London Fletcher, LB, Redskins (hamstring): Fletcher missed a huge chunk of the second half Sunday after hobbling to the sideline.

Carroll:Fletcher remains a very active and mobile LB at age 37, so a hamstring strain is going to effect him more than most. Fletcher appeared to be in significant pain as he pulled up and grabbed very high on the muscle. Those are bad signs, but scans will give more information. If Fletcher is not available for this week's game against the Steelers, it will be a big plus for the Steelers offense -- especially their shaky run game.

Who takes his spot?: Veteran Lorenzo Alexander would slot into the starting lineup, if the Redskins indeed find themselves without Fletcher's services.

• Fred Davis, TE, Redskins (Achilles): Davis collided with the Giants' Antrel Rolle, hopped off the field and then was carted to the locker room.

Carroll:Davis ruptured his Achilles tendon and is done for the season. Hopefully, he saw that Terrell Suggs came back on Sunday and played better than most expected. There was one play where Suggs went up and tipped a pass. He jumped, landed, hopped to quickly turn and see where the ball went. It was a perfect test of his rebuilt Achilles and he passed. Now here's the issue of timing -- Suggs came back in six months. Davis could, but there's not much for a TE to do in April. He should be 100 percent well before training camp.

Who takes his spot?: Reports started circulating Sunday night that the Redskins were close to bringing Chris Cooley back into the fold.

• Joseph Morgan, WR, Saints (chest): Morgan was taken to the hospital Sunday after suffering a chest injury in the third quarter.

Carroll:Morgan went into Bruce Lee mode for a TD that will go on the shelf next to Jerome Simpson's flip and John Elway's helicopter spin. He left later in the game for scans on his chest that were said to be precautionary. While it is unclear what happened to cause the injury, these kinds of injuries have to be taken very seriously. There's no way to put a timeline on it yet.

Who takes his spot?: Morgan's only fourth or fifth in the Saints' wide receiver pecking order anyway, so they won't be left scrambling if he's out.

• Phil Costa, C, Cowboys (ankle): Costa had to be carted off the field after suffering what looked like an ugly ankle injury. The Cowboys announced that he suffered a partial dislocation of his ankle, with an MRI set for Monday.

Carroll:Add an ankle injury to the litany of maladies Costa has dealt with this season. It's impossible to say if this is related, but Costa appeared both angry and in pain as he left the field. The demands of the position make it tough to play with reduced mobility.

Who takes his spot?: Ryan Cook replaced Costa for the remainder of Sunday's win in Carolina. He would continue to handle the center duties going forward.